The bar room has a blunter term than ‘problem’: let’s call it urine-artist. It’s easy to be lugubrious about alcoholism – it’s a long-winded affliction, and you can never be sure it’s gone.

Relapse. That lovely word for something very nasty and all too common. In the series just concluded, Rob is drinking again. Furtively. Just coping but on a slippery slope. His life is one of low level moral degradation. Putting the dirty washing in the machine he fishes out a miniature bottle of vodka from the soiled pile and gulps it, hating himself.

What did Hemingway say? “A man does not exist until he’s been drunk”. Papa wasn’t thinking of secret drinkers.

There are three telling moments in the last instalment. One is Carrie Fisher, Rob’s mother, telling him that if he drinks a little he’ll drink a lot, and if he drinks a lot he’ll beat up his wife. Just like his father did (news to Rob).

The second is Rob, glumly waiting for an AA meeting to start. We see it through his eyes. They are not him, these down and outs. I remember the same feeling. Me? A Doctor of Philosophy and eminent scholar at University College London? In this company of such losers? Never.

Rob is saved by a text message from his friends, inviting him to join them for a Chinese. He leaves the meeting, eats – and drinks. Frightened, he can’t finish his meal. Then the climax. His wife, Sharon gets absolutely blotto. Rob drives to pick her up. There’s a crash. Someone, even more out of their head than Rob, has piled into him, broadside. The police, he whimpers, will breathalyse him and he will fail. Sharon takes him to her breast. It’s hopeless. Or is it?

I too have had my struggles. In my drinking days I did things that I didn’t know were in me, or any sane human. I was lucky not to be killed on the road. But the main risk was suicide when consciousness and conscience returned. Delaney has also confessed as much.

On January 24, 1983 I woke up surrounded by empty bottles in an empty apartment. My family – a wife of 15 years and child – had wisely “saved themselves”, as the pamphlets advise.

Then mid-forties, my drinking had been excessive, but more or less under control, for a decade – a long time for the human liver. But it was now spinning out of control, initially in the form of after hours or weekend binges (what, for normal married men, would be “family time”).

At my loved ones’ insistence I had previously been “seen” at Maudsley hospital, armed with a letter of introduction from a senior physician friend (I was no common-or-garden drunk, for God’s sake). The letter cut no ice. And the prescription was drastic: I must give up drinking altogether. As well as stop breathing?

A fortnightly one-to-one meeting (hours in the ghoulish waiting room for 40 minutes’ counselling) would keep me to this. The theory was that, if I could stay off the booze for 18 months, the “prognosis” was good for permanent recovery. Perhaps they were right. I never made it to the finishing line.

This was 1980. I manfully went on a year’s white-knuckle ride as a “dry drunk”, as AA jargon puts it. It didn’t last, corroding gradually, like an old dam giving way under the pressure of that vast lake of drink on the other side. I would manage six weeks (a painfully long period for an abstaining alcoholic) before jumping out of the groove – usually for an explosively brief bout, but long enough to smash things up. Remorse would get me back on the wagon, but for a shorter period than the last.

By January 1983, I was on the terrible merry-go-round of what AA calls “periodics”. Sober for weeks, sodden-drunk for days, bitterly remorseful, then sober again.

This is a peculiarly destructive phase. Having lapsed, one drinks to madly toxic levels – making up for lost time, suffused with guilt and apprehensive of the dry weeks to come before the next glorious release. The gross drunkenness shatters the trust others put in you. Usually after the third or fourth such episode they give up on you. I was well past that threshold.

Professionally, I would still be classified as a “high functioning” alcoholic. There were occasional disasters: slurred lectures, student complaints, missed meetings, insulted colleagues, dinner-party faux pas (some of which still make me groan out loud today).

Yet I could just about cope. I was experienced enough, after 20 years, to fly on automatic pilot. It helped that in academic life you largely devise your own schedule. Cannily (alcoholics love to think of themselves as smart operators), I ensured that the bulk of my tutorials were in the hungover but clear-headed morning, before the dangerous fog of the lunchtime session descended.

But domestically, it was something else. One of the problems about problem drinking is that you tend to be at your drunkest and least civilised at night – when you go home. If your family is still around, “scenes” are inevitable.

Few women nowadays wield the cartoonist’s rolling-pin, or throw crockery at their spouse’s head. But their long-brewed disapproval scalds the alcoholic (who will already be feeling remorse) like molten lead.

What defence do you have? None. Guilt makes the drunk quarrelsome and few alcoholics – when drunk and quarrelsome – are not violent, verbally and (​at their worst) physically. Anger is, late in the game, exacerbated by sexual paranoia (the alcoholic’s impotence translates into jealousy of Othello-like intensity). And, of course, there is the sheer nastiness of the Edward Hyde everyone has inside them. He thrives on booze.

Yet most career alcoholics have what is called a “moment of clarity”. A fork in the road. Take one path and it’s the morgue, locked ward or skid row. The other, harder path is recovery, with relapse an ever-present risk.

I finally cleaned up with the help of AA in America. They invented the ‘fellowship’ and, in my experience, do it best. My wife and child took the risk of rejoining me there for a new life. I got a second chance. A month’s more drinking, perhaps even a day’s more, would have done for me.

But it’s not easy. In 2001, long after I had returned to UCL as Lord Northcliffe Professor of English Literature, I wrote a “drunkalog”, called Last Drink to LA. One scene in the book involves criminals and utter sexual depravity. There’s no mystery about why I wrote it down; it happened. But it scorches me, even now, to recall the truth.

So why publish this squalid thing? Firstly, unresolved anger – the unexploded bomb thesis. Unlike Delaney, I am not on medication, nor am I consulting a shrink. Perhaps I should be.

But the stronger reason, I think, is public confession. I want to be forgiven. It’s pathetic – but for me, and I suspect Delaney, irresistible. Most alcoholics, in my experience (and I’ve heard thousands of them talk), want to tell all and covertly hope to receive what clemency – or at least understanding – they can be given. The downside? No one will ever think as well of you as they once did.

But then, no one ever said alcoholism was easy. Even the long dry years. Cheers.